Stomatal Crypts Have Small Effects on Transpiration: A Numerical Model Analysis

Abstract

Stomata arranged in crypts with trichomes are commonly considered to be adaptations to aridity due to the additional diffusion resistance associated with this arrangement; however, information on the effect of crypts on gas exchange, relative to stomata, is sparse. In this study, three-dimensional Finite Element models of encrypted stomata were generated using commercial Computational Fluid Dynamics software. The models were based on crypt and stomatal architectural characteristics of the species Banksia ilicifolia, examined microscopically, and variations thereof. In leaves with open or partially closed stomata, crypts reduced transpiration by less than 15% compared with nonencrypted, superficially positioned stomata. A larger effect of crypts was found only in models with unrealistically high stomatal conductances. Trichomes inside the crypt had virtually no influence on transpiration. Crypt conductance varied with stomatal conductance, boundary layer conductance, and ambient relative humidity, as these factors modified the three-dimensional diffusion patterns inside crypts. It was concluded that it is unlikely that the primary function of crypts and crypt trichomes is to reduce transpiration.

Plant mineral nutrition in ancient landscapes: high plant species diversity on infertile soils is linked to functional diversity for nutritional strategies

“…; A.M. Grigg et al (unpubl. )) It is very likely that this trait has been the driving force for the evolution of stomatal crypts, whose depth correlates strongly with the thickness of the leaves in which they are found (Hassiotou et al 2009b;Roth-Nebelsick et al 2009). …”

Wettability, Polarity, and Water Absorption of Holm Oak Leaves: Effect of Leaf Side and Age

“…The epidermis of plants has been found to have a major degree of physical and chemical variability and may often contain specialized cells such as trichomes or stomata (Roth-Nebelsick et al, 2009;Javelle et al, 2011). Most aerial organs are covered with an extracellular and generally lipid-rich layer named the cuticle, which is typically composed of waxes embedded in (intracuticular waxes) or deposited on (epicuticular waxes) a biopolymer matrix of cutin, forming a network of cross-esterified hydroxy C 16 and/or C 18 fatty acids, and/or cutan, with variable amounts of polysaccharides and phenolics Yeats and Rose, 2013).…”

Role of exogenous folic acid in alleviation of morphological and anatomical inhibition on salinity-induced stress in barley

“…Stomata are apertures that regulates moisture balance, thus they are very important in maintaining the water balance of plants (Berry et al, 2010). Furthermore, stomatal density is proportional to gas exchange rate (Roth-Nebelsick et al, 2009). So, we think that increasing the number and sizes of stomatal apertures on both sides of leaves through FA treatment will have positive impact on photosynthesis rate.…”